Réponse :
Bonjour:
a. At the beginning of the 19th century, children mustn't sit down to eat in cotton mills.
b. They should work in terrible conditions.
c. Only rich children can go to school.
d. Poor children should not have fun.
Explications :
Pour la notion ''interdiction''
tu utilises ces verbes:
must not/ cannot
example: you must not smoke on school grounds.
Pour la notion ''obligation''
tu utilises ces verbes:
must / have to / should
example: you have to finish your homework.
Pour la notion ''permission''
tu utilises ces verbes:
could / may / can
example: can i borrow your pen?